The present invention relates to a process for producing 3,5-dichloroaniline which is remarkably advantageous in the industrial operation.
The 3,5-dichloroaniline is useful as an intermediate for various agricultural chemicals, dyes and medicines. It has been known to produce 3,5-dichloroaniline by chlorinating p-nitroaniline and diazotizing and reducing the reaction product. However the raw material is expensive and many steps are required in the preparation and the volume of waste water in the process is large. The improvement of the process has been needed.
It has been disclosed to produce 3,5-dichloroaniline by reacting 1,3,5-trichlorobenzene with lithium amide in Journal of Organic Chemistry 24 595 to 598 (1959). The process is not advantageous from the economical viewpoint because a long reaction time such as 18 hours is needed but a large amount of the unreacted material remains in the reaction mixture.
The inventors have studied industrial processes for producing 3,5-dichloroaniline through a benzyne intermediate by reacting 1-bromo-2,4-dichlorobenzene with a metal amide in liquid ammonia.